Staple stick advancing device



June 8, 1957 w. A. FORRESTER 86 STAPLE STICK ADVANCING DEVICE 7 Filed May 3, 1954 Ell" E WILL/HM FLFORKESTE/g 5/ A I United States Patent STAPLE STICK ADVANCING DEVICE William A. Forrester, Herrin, 111., assignor to International Staple and Machine Company, Herrin, Ill., a corporation of Pennsylvania Application May 3, 1954, Serial No. 427,171

2 Claims. (Cl. 1-3) This invention relates to improvements in staple stick advancing devices and, in particular, is concerned with a mechanism for retaining said device in a staple machine magazine. The advancing device which is conventionally called a magazine pusher is, by means of this invention, adapted to be inserted into the magazine in a simple and expeditious manner without any danger of its being dislodged by accidental forces.

In the past, magazine pushers have been conventionally used in magazines for advancing a staple stick to feed staples to the staple head in the usual clinching operation. Such magazine pushers are generally detachable so that they may be inspected for proper operation, and it is desirable that the securing of the pusher to the magazine be effected in a simple manner. This has led to the problem in the past of securing the pusher in such a manner that it will not be dislodged by accidental jarring and other forces incidentally encountered in normal operation.

A conventional securing of a pusher has been to efiect a rotary lock engagement of the pusher with cooperating flanges in the magazine which has made the pusher susceptible to sudden jars that would tend to rotate the pusher in relation to the magazine, and would thereby allow the pusher to spring outwardly and away from the magazine and cause an interruption in the operation such that a new securing would be required. This problem has been obviated by the present invention which contemplates a spring-like pusher having opposed teats which can be sprung in toward one another and caused to engage either inturned flanges or associated recesses in the magazine for a locking fit.

The particular pusher of this invention can be positioned within the magazine merely by depressing the sides of the retaining spring in a very simple operation, and wherein the pusher in the locked position resists any rotary forces tending to unlock it. The retaining spring is made of conventional strap metal having a spring-like resiliency, and is of very simple construction so that the expense and labor involved in the construction is substantially reduced, with, at the same time, a wide adaptability for the securing and locking engagement being realized by this invention.

Accordingly, it is an object of this invention to provide a simple device to operate magazine pusher which can be used for locking the same in a conventional staple machine magazine to prevent accidental dislodgement and unlocking of the pusher.

It is yet a further object of this invention to provide a magazine pusher having a retaining spring lock which will resist, when in the locked position in the magazine, any accidental jars or other forces which would tend to unlock it so that it can be locked only when a particular characterized unlocking operation is performed upon it.

Still another object of this invention is to provide a spring-like retaining device for a magazine pusher made of a strap-like material wherein the retaining device resists any rotary motions tending to unlock it.

Still another object of this invention is to provide a retaining device for a magazine pusher made of straplike spring metal having teats which are adapted to engage the magazine for locking engagement to resist the unlocking forces of any accidental jars.

Yet a further object of this invention is to provide a spring-like retaining device for a magazine pusher made of a spring-like strap material which is adapted to be used in different forms of magazines, and can be made from conventional materials of construction with a minimum of cost and labor.

Other objects of this invention will appear in the detailed description which follows and will be further apparent to those skilled in the art.

In the accompanying drawings there are shown two embodiments of the magazine pusher of this invention which are adapted to be used in slightly different forms of staple magazines. These two modifications are illustrative of the retaining device for the magazine pusher, and it is to be realized that these modifications are shown for the purposes of description only, and that the invention is not limited thereto.

In these drawings:

Fig. 1 is a top plan view of one form of magazinev pusher;

Fig. 2 is a side elevation of the magazine pusher shown in Fig. 1; s

Fig. 3 is a top plan view showing the magazine pusher of Fig. 1 locked in one form of a magazine for a staple machine;

Fig. 4 is an enlarged view partly in section showing theleft end of the assembly of Fig. 3 in elevation;

Fig. 5 is a cross sectional view taken on the line 55 of Fig. 4; i

Fig. 6 is a top plan view showing a modified form of retaining device adapted to be used in a magazine pusher of the same type as shown in Fig. 1;

Fig. 7 is a top plan view partly in section showing the modified retaining device of Fig. 6 used in a slightly difierent type of stapling machine magazine;

Fig. 8 is an enlarged view partly in section of an elevation of the assembly of Fig. 7; and

Fig. 9 is a view in section taken on the line 9--9 of Fig. 8.

Reference will now be had to the drawings and, in particular, Figs. 1 to 5 showing the first form of the retaining device for the magazine pusher. The magazine pusher is generally indicated at 20. It includes a rod21 having a head-22 which acts as a stop for a slidable staple advancing head 23. At the other end of the rod is attached a retaining device generally indicated at 24 that acts as a base for the helical spring 25 which abuts at its other end against the slidable advancing head.

The advancing head 23 is of a generally U-shaped configuration with the open end of the U being at the bottom of the head. The head is, as mentioned previously, slidable upon the rod 21 and is urged toward the 22 by the action of the helical spring 25.

The retaining device 24 is also of a generally U-shaped configuration and has two legs 26 and 27 which are alike in all respects, and are provided with grooves 43 and 44 adjacent teats 28 and 29, respectively. The legs 26 and 27 are adapted to be sprung in toward one another for a purpose which will appear below.

In Figs. 3 to 5 a staple stick magazine is shown generally indicated at 31. This magazine is adapted to feed a stick of staples of the conventional U-shaped configuration to the right to the staple machine head (not shown) which is at the right end of the magazine and may be of any conventional design. The magazine 31 has an outer ed ad.

frame 32 which is of a generally so-called C-shaped rectangular cross section having inturned flanges 33 and 34 at the top, as shown in Fig. 3. The frame has a bottom base 35 upon which is mounted inversely a U-shaped staple guide track 36. This guide track has upstanding legs 37 and 38 connected by a base 39 which is fastened to the frame base 35-. The end of the staple guide track is provided with two inturned flanges 41 and 42 for the purpose of securing a magazine pusher therein.

As shown in Fig. 3, the teats 28 and 29 of the retaining device engage the inturned flanges 41 and 42, and the rod 21 fits in the interior of the staple guide track with the staple advancing head 23 fitting thereover and riding thereon.

The 'modified form of a retainer for the magazine pusher is shown in Figs. 6 to 9 and is adapted to be used in a somewhat different type of magazine. In Fig. 6 the retainer is shown generally indicated at 45 and includes two legs 46 and 47 connected to teats 48 and 49, respectively. These teats have no grooves next to the legs, as in the grooves 43 and 44 shown in Fig. l, and, in addition, the legs 46 and 47 are slightly bowed so that they angle away from. one another. The retainer 45 is connected to a rod 21 and the rest of the magazine pusher is identical with the magazine pusher 20 of Fig. 1.

The magazine is shown in Figs. 7, 8 and 9 and is generally indicated at 51. This magazine is similar in construction to the magazine 31 of Fig. 3 with the exception that the guide track indicated at 53 has no inturned flanges at its left end. The frame 54 of the magazine 51 is similar to the frame 32 of the magazine 31, and the track 53 is mounted upon it in identical manner. However, the frame 54 is provided at its sides with two slots 55 and 56.

The magazine pusher is positioned within the magazine 51 in a similar manner shown in Fig. 3 with the retaining device 45 being locked within the frame of the magazine by. engagement of the teat 48 in the slot 55, and teat 49 in the slot 56. The engagement is secure and effective against any rocking or pivotal action because of the engagement of the opposed teats 48 and 49 throughout their extent from top to bottom in the respective slots in which they are fitted.

Use

When it is fully extended against the stick of staples at the right end of the magazine the retainer device is pressed together by the fingers of the operator at a position adjacent the teats 28 and 29 so that these teats are caused to engage the inturned flanges 41 and 42 adjacent the grooves 43 and 44 in the manner shown in Fig. 3. When this is effected the magazine pusher is firmly locked within the magazine. After this has been accomplished the magazine pusher is ready to be used in the conven- 4 tional manner. Then the magazine pusher causes the staple stick to be biased toward the right end of the maga zine so as to feed the staples to the stapling head in the usual fashion.

The retainer 45, shown in Figs. 6 to 9, is adapted to be used in the modified magazine shown in Fig. 7 in a very similar manner to that above described for the retainer 24. Here the staple guide track 53 has no inturned ends to receive the teats of the retainer, and for this reason the frame 54 of the magazine is provided with the vertical slots 55 and 56.

Accordingly, in this modification, the legs 46 and 47 of the retainer are depressed after the advancing head has been positioned upon the staple track and moved to the right of the magazine so that the teats 48 and 49 can be properly engaged within the said slots. After this has been done, the retainer 45 is firmly locked in place. It cannot be rocked out of position or unlocked until the legs 46 and 47 are depressed toward one another in a characterized fashion and the magazine pusher is then removed.

This invention has been described for two different and modified types of staple magazines, and it is clear that the retainer for the magazine pusher can be further modified to provide for proper locking in other variations. Such modifications and variations of this invention will readily appear from the above description, will be further apparent to those skilled in the art, and are within the teachings of the invention as defined in the claims appended hereto.

What is claimed is:

l. A magazine staple pusher adapted to be used in a staple magazine having a staple guide track provided with vertically extending inturned flanges at its end, said pusher having a staple advancing head slidable on an elongated rod connected to a retainer element, means biasing said head away from said retainer element and opposed depressible locking means on the end of said retainer element adapted to engage said flanges to prevent rotational and longitudinal movement of said retainer element for secure locking engagement.

2. A retainer element adapted to be used in a magazine staple pusher for a stapling machine magazine having a staple guide track provided with vertically extending inturned flanges at its end, said pusher having an elongated rod and a staple advancing head slidable on said rod and biasable toward one end of said rod, said retainer element being adapted to be connected to the other end of said rod and having two legs depressible toward one another and having means at their ends adapted to lock said retainer to said magazine, said means including recesses in each of said legs opening away from the other leg adapted to engage said flanges to prevent rotational and longitudinal movement of said retainer element for secure locking engagement.

References Cited in the file of this patent UNITED STATES PATENTS 2,268,102 Attula Dec. 30, 1941 2,462,623 Flamm Feb. 22, 1949 2,535,482 Boroughs Dec. 26, 1950 

